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Braket operation

  1. Jul 26, 2012 #1
    Is this operation legal?

    [itex]\langle A_1|BA|A_2\rangle=A_2\langle A_1|B|A_2\rangle[/itex]

    If so, please elaborate on that.

  2. jcsd
  3. Jul 26, 2012 #2


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    If [itex]|A_2 \rangle[/itex] is an eigenvector of the operator [itex]\mathbf{A}[/itex] with eigenvalue [itex]A_2[/itex] then your operations are correct.
  4. Jul 26, 2012 #3

    \langle A_1|BA|A_2\rangle=\langle A_1|B\rangle \langle A|A_2\rangle=
    \langle A_1|B\rangle A_2=A_2\langle A_1|B\rangle


    Thank you.
  5. Jul 26, 2012 #4
    No. You are mixing up operators with bras and kets. It looks like A and B are supposed to be operators. If so, the expressions |A>, <A|, |B>, or <B| make no sense. Operators are neither bras nor kets.
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